UI Automation Support for the CheckBox Control Type
This topic provides information about Microsoft UI Automation support for the CheckBox control type.
A check box is an object used to indicate a state that users can interact with to cycle through that state. Check boxes either present a binary (Yes/No), (On/Off), or tertiary (On, Off, Indeterminate) option to the user.
The following sections define the required UI Automation tree structure, properties, control patterns, and events for the CheckBox control type. The UI Automation requirements apply to all check box controls, whether Microsoft Windows Presentation Foundation (WPF), Microsoft Win32, or Windows Forms.
This topic contains the following sections.
- Required UI Automation Tree Structure
- Required UI Automation Properties
- Required UI Automation Control Patterns
- Required UI Automation Events
- DefaultAction
- Related Topics
Required UI Automation Tree Structure
The following table depicts the control view and the content view of the UI Automation tree that pertains to check box controls and describes what can be contained in each view. For more information about the UI Automation tree, see UI Automation Tree Overview.
| Control View | Content View |
|---|---|
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|
Required UI Automation Properties
The following table lists the UI Automation properties whose value or definition is especially relevant to the CheckBox control type. For more information about UI Automation properties, see UI Automation Properties for Clients.
| UI Automation Property | Value | Notes |
|---|---|---|
| UIA_AutomationIdPropertyId | See notes. | The value of this property needs to be unique across all controls in an application. |
| UIA_BoundingRectanglePropertyId | See notes. | The outermost rectangle that contains the whole control. |
| UIA_ClickablePointPropertyId | See notes. | Supported if there is a bounding rectangle. If not every point within the bounding rectangle is clickable, and you perform specialized hit testing, override and provide a clickable point. |
| UIA_ControlTypePropertyId | CheckBox | This value is the same for all UI frameworks. |
| UIA_IsContentElementPropertyId | TRUE | The value of this property must always be TRUE. This means that the check box control must always be included in the content view of the UI Automation tree. |
| UIA_IsControlElementPropertyId | TRUE | The value of this property must always be TRUE. This means that the check box control must always be included in the control view of the UI Automation tree. |
| UIA_IsKeyboardFocusablePropertyId | See notes. | If the control can receive keyboard focus, it must support this property. |
| UIA_LabeledByPropertyId | Null | Check box controls are self-labeling. |
| UIA_LocalizedControlTypePropertyId | See notes. | Localized string corresponding to the CheckBox control type. The default value is "check box" for en-US or English (United States). |
| UIA_NamePropertyId | See notes. | The value of the check box control's IUIAutomationElement::CurrentName (or IUIAutomationElement::CachedName) property is the text that is displayed beside the box that maintains the toggle state. |
Required UI Automation Control Patterns
The following table lists the UI Automation control patterns required to be supported by all check box controls. For more information on control patterns, see UI Automation Control Patterns Overview.
| Control Pattern/Pattern Property | Support/Value | Notes |
|---|---|---|
| IToggleProvider | Required | Allows the check box to be programmatically cycled through its internal states. |
Required UI Automation Events
The following table lists the UI Automation events that check box controls are required to support. For more information on events, see UI Automation Events Overview.
| UI Automation Event | Notes |
|---|---|
| UIA_AutomationFocusChangedEventId | None |
| UIA_BoundingRectanglePropertyId property-changed event. | None |
| UIA_IsOffscreenPropertyId property-changed event. | If the control supports the IsOffscreen property, it must support this event. |
| UIA_IsEnabledPropertyId property-changed event. | If the control supports the IsEnabled property, it must support this event. |
| UIA_StructureChangedEventId | None |
| UIA_ToggleToggleStatePropertyId property-changed event. | None |
DefaultAction
The default action of the check box is to cause a radio button to become focused and toggle its current state. As mentioned previously, check boxes either present a binary (Yes/No or On/Off) decision to the user or a tertiary (On, Off, Indeterminate). If the check box is binary the default action causes the "on" state to become "off" or the "off" state to become "on". In a tertiary state check box the default action cycles through the states of the check box in the same order as if the user had sent successive mouse clicks to the control.